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arXiv · 0908.1454

Effect of bath temperature on the quantum decoherence

Peihao Huang·Hang Zheng
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Abstract

The dynamics of a qubit in two different environments are investigated theoretically. The first environment is a two level system coupled to a bosonic bath. And the second one is a damped harmonic oscillator. Based on a unitary transformation, we find that the decoherence of the qubit can be reduced with increasing temperature $T$ in the first case, which agree with the results in [Phys. Rev. Lett. 100, 120401], whereas, it can not be reduced with $T$ in the second case. In both cases, the qubit dynamics are changed substantially as the coupling increases or finite detuning appears.

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Peihao Huang, Hang Zheng. 2013-11-04. Effect of bath temperature on the quantum decoherence. https://doi.org/10.1016/j.cplett.2010.10.009

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